JP4666787B2 - Vibration detection apparatus and image shake correction apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a vibration detection apparatus and an image shake correction apparatus having a vibration detection means for detecting vibration.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there has been proposed an apparatus for performing image stabilization by suppressing vibration due to camera shake correction, that is, camera shake or the like, including a camera. A typical one of the shake correction methods used for cameras and the like is to drive a part or all of the photographing optical system based on camera shake information detected by a shake sensor on the image plane. This is to suppress image blur.
[0003]
Here, an angular velocity sensor or an acceleration sensor is generally used as the shake sensor. Since such an angular velocity sensor or an acceleration sensor itself outputs only a minute voltage with respect to a given vibration, an appropriate amplifier is provided outside the sensor to output a necessary voltage. Yes. However, sensors that detect such vibrations, especially piezoelectric vibration gyros that are commonly used in cameras, etc., have a stationary output voltage when no vibration is applied (the reference voltage of the sensor and the stationary output voltage). Difference = null voltage) varies significantly depending on the operating temperature, particularly due to variations in individual vibration gyros and changes in the usage environment. Therefore, a problem especially when the power is turned on is that when the output signal is amplified to the necessary voltage, the null voltage is amplified, and the signal is saturated particularly when a high gain amplifier is used. There is a possibility that.
[0004]
In order to solve the above-mentioned problem, a conventionally disclosed method is to provide a high-pass filter circuit that cuts from the output of the angular velocity sensor a frequency lower than an allowable low frequency with respect to the vibration frequency to be detected. A method of amplifying a signal that has passed through a circuit with an amplifier is generally used.
[0005]
Further, as an improvement over the above-described conventional example, Japanese Patent Laid-Open No. 10-228043 discloses a vibration detection device that eliminates a large-capacitance capacitor constituting a high-pass filter circuit and is advantageous in terms of cost and mounting. This is because the output from the vibration gyro is input to the microcomputer through a circuit composed of a low-pass filter circuit, an adder and an amplifier circuit, and the microcomputer is biased with respect to whether the output signal of the circuit exceeds a predetermined level range and a reference level. It is to determine whether or not. When it exceeds the predetermined level range or is deviated from the reference level, a control signal is generated from the microcomputer, and the output of the D / A converter is controlled by the signal. The output of the D / A converter is connected to the adder and adjusts the output signal within a predetermined level range and a reference level. With such a configuration, an unstable output when power is turned on is amplified without being saturated, and a desired output value is obtained.
[0006]
FIG. 7 shows a conventional example in which an image blur correction apparatus is applied to an interchangeable lens of a single-lens reflex camera as an example of a configuration for compensating for an offset component of a sensor using a D / A converter as described above.
[0007]
FIG. 7 is a block diagram showing specific circuit configurations of a lens microcomputer and a shake correction system as the lens electrical system.
[0008]
The output from the vibration gyro 1 which is an angular velocity sensor for detecting shake is A / D converted by the lens microcomputer 4 through the amplifier 3 composed of the resistor R1, resistor R2, resistor R3, capacitor C1, capacitor C2, and operational amplifier 2. Is input to the device 5. In the amplifying unit 3, the amplification factor is determined by (R3 / R1), and a secondary high-frequency cutoff filter is formed for noise removal. The D / A converter 7 includes two 8-bit D / A converters 7a (D / A (1)) and 7b (D / A (2)) and resistors R4 and R5. A resistor R4 is connected to the output end of the D / A converter 7a, and a resistor R5 is connected to the output end of the D / A converter 7b. The other ends of both resistors are both non-inverting input terminals of the operational amplifier 2. It is connected to the. Here, the resistance ratio between the resistor R4 and the resistor R5 is set to, for example, about “R4: R5 = 1: 110”. This is determined in consideration of the resolution of the offset compensation control.
[0009]
At the initial stage of turning on the power, the offset removing means 6 (comprising the output saturation avoidance control unit 6a, the control data storage unit 6b, and the data selection / control unit 6c) is used for the offset component compensation calculation of the vibration gyro 1. In operation, the offset removing means 6 controls the outputs of the D / A converter 7a and the D / A converter 7b. The resistance-divided outputs of the D / A converters 7a and 7b are connected to the non-inverting input terminal of the operational amplifier 2 of the amplifying unit 3, and the output of the D / A converter 7 according to the output of the A / D converter 5. Is controlled, the correction voltage is controlled, and the offset component of the vibration gyro is compensated. Thereafter, it is converted into an angular displacement signal through a high-pass filter (HPF) 8 and an integrator 9. Then, the output of the position sensor 10 that detects the position of the correction lens (via the amplifier 11 and the A / D converter 12) is added with a reverse polarity and subjected to feedback calculation, and the signal is output from the output port of the lens microcomputer 4 as a PWM signal. Is output via the PWM signal converter 13 and the correction lens is driven by the coil driver 14 to cancel the image blur.
[0010]
[Problems to be solved by the invention]
FIG. 8 is an example of an output waveform when a large output is not applied to the vibration gyro and the output is stable ((a) when stationary) and when a large vibration such as panning occurs ((b) during panning). .
[0011]
When stationary in FIG. 8A, the output of the vibration gyro is normally output by adding + α (or −α: α is a null voltage component) with respect to a predetermined reference voltage. The above-described offset compensation calculation is performed based on this α. However, at the time of panning in FIG. 8B, + β (or −β), which is a panning component, is added in addition to α. Therefore, when offset compensation is performed in such a state, calculation is performed using α + β (or α−β, β−α, −α−β) as a reference value.
[0012]
In other words, when the above-mentioned offset compensation calculation is performed in the panning or large shake state by the image blur correction device, the addition amount of the panning output component and the true sensor offset component is regarded as the sensor offset amount at that time, and the offset compensation calculation is performed. Therefore, if the panning operation or the large shake operation is stopped after the offset compensation calculation is finished, there is a possibility that the output may be greatly deviated from the target value, and in some cases, the output is saturated.
[0014]
  The present inventionIsAn image blur correction device that does not adversely affect the subsequent image blur correction operation even if the offset component that is superimposed on the shake signal is removed when the device is panned or shaken.The purpose is to do.
[0015]
[Means for Solving the Problems]
  The image blur correction device of the present invention isVibration detecting means for detecting vibration; means for outputting a correction voltage from which an offset component of the output of the vibration detecting means is removed;Based on the correction voltageOffset removing means for removing an offset component of the output of the vibration detecting means;,In the image blur correction apparatus having the above, after operating the offset removing meansIn addition, it is determined whether the output from the means for outputting the correction voltage is within the first determination range within the first determination time, and if it is within the determination condition, the start of the image stabilization operation is instructed. If it is not within the determination condition, the offset determination unit is operated again, and a first determination is performed again to determine whether the offset is within the first determination range within the first determination time. The control means operates after instructing the start of the image stabilization operation, determines whether the output of the comparison means is within the second determination range within the second determination time, and within the determination condition If there is, if it is not within the determination condition, the image stabilization operation is temporarily interrupted, and the second determination and control means for operating the offset removal means again, The determination time is longer than the first determination time, and the second determination time is longer than the first determination time. Range is characterized wider than the first determination range.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on illustrated embodiments.
[0018]
FIG. 1 is a block diagram according to an embodiment of the present invention, taking as an example a case where an image shake correction apparatus is mounted in an interchangeable lens of a single-lens reflex camera.
[0019]
In FIG. 1, reference numeral 101 denotes a lens microcomputer, which receives communication from the camera body side through communication contacts 109c (for clock signal) and 109d (for body-to-lens signal transmission). The shake correction system 102, the focus drive system 104, and the aperture drive system 105 configured as described above are operated. The shake correction system 102 includes a shake sensor 106 for detecting shake, a position sensor 107 for detecting a correction lens displacement, and a control signal calculated by the lens microcomputer 101 based on outputs of the shake sensor 106 and the position sensor 107. The image forming apparatus includes a shake correction drive system 108 that drives a correction lens to perform a shake correction operation. Reference numeral 124 (SWIS) denotes an anti-vibration switch for selecting the shake correction operation. When the shake correction operation is selected, the anti-vibration switch 124 is turned ON.
[0020]
The focus drive system 104 performs focusing by driving a focus adjustment lens according to a command value from the lens microcomputer 101. The aperture driving system 105 performs an operation of reducing the aperture to a set position or returning to an open state according to a command value from the lens microcomputer 101. The lens microcomputer 101 also communicates information about the lens internal state (focus position, aperture value state, etc.) and information about the lens (open aperture value, focal length, data necessary for distance calculation, etc.) 109e for communication. It is also transmitted from the lens (for body signal transmission) to the body side.
[0021]
The lens microcomputer 101, the shake correction system 102, the focus drive system 104, and the aperture drive system 105 constitute a lens electrical system 110. The lens electrical system 110 is supplied with power from an in-camera power source 118 through a power contact 109a and a ground contact 109b.
[0022]
  Inside the camera body, as a camera body electrical system 111, a distance measurement unit 112, a photometry unit 113, a shutter unit 114, a display unit 115, other control units 116, and management and exposure of these operations start and stop, etc. A camera microcomputer 117 that performs calculation, distance measurement calculation, and the like is incorporated. theseElectric system in camera bodyThe power is also supplied to the power source 111 from the in-camera power source 118. 121 (SW1) is a switch for starting photometry and distance measurement, 122 (SW2) is a release switch for starting a release operation, and these are generally two-stage stroke switches. The switch 121 is turned on by the first stroke of the release button, and the release switch 122 is turned on by the second stroke. Reference numeral 123 (SWM) denotes an exposure mode selection switch. The exposure mode can be changed by turning the switch ON or OFF, or by simultaneously operating the switch 123 and other operation members.
[0023]
FIG. 2 is a block diagram illustrating specific circuit configurations of the lens microcomputer 101 and the shake correction system 102 of the lens electrical system 110.
[0024]
  Since the configuration is almost the same as the configuration of the block diagram of FIG. 7, the reference numeral of FIG. 7 is added with a number, and detailed description thereof is omitted. As a part different from FIG. 7, the first determination / control unit 520 and the second determination / control unit 521 include an A / D converter 505 and a high-pass filter (HPF).508It is a point that is intervened during.
[0025]
FIG. 3 is a flowchart showing a specific processing operation in the lens microcomputer 504 of FIG.
[0026]
  Here, the image blur correction operation is performed by an interrupt process that occurs at regular intervals. Then, control in the first direction, for example, the pitch direction (vertical direction) and control in the second direction, for example, the yaw direction (lateral direction) are alternately performed. When an interrupt occurs, the lens microcomputer 504 will display FIG.InThe operation from step # 101 in the flowchart shown is started.
[0027]
First, in step # 101, it is determined whether the current control direction is the pitch direction or the yaw direction. If it is in the pitch direction, the process proceeds to step # 102, a data address is set so that various flags, coefficients, calculation results, etc. can be read and written as pitch data, and the process proceeds to step # 104. If it is in the yaw direction, the process proceeds to step # 103, and a data address is set so that various flags, coefficients, calculation results, etc. can be read and written as yaw data, and the process proceeds to step # 104.
[0028]
In step # 104, the output of the vibration gyro 501 that is an angular velocity sensor is A / D converted, and the result is stored in AD_DATA defined in the RAM. Then, in the next step # 105, it is determined whether or not an instruction to start image blur correction has been issued. For example, image blur correction is started by AND of the switch SWIS and the switch SW1 ON. If an instruction to start image blur correction has been given, the process proceeds to step # 106, and if no instruction has been given, the process proceeds to step # 118. Here, an instruction to start image blur correction is given, and it is assumed that the process proceeds to step # 106. At the same time, a power feeding operation is performed on the vibration gyro 501, the amplifying unit 503, the D / A converter 507a, and the D / A converter 507b (not shown).
[0029]
In step # 106, the offset compensation calculation end flag is determined. When the offset compensation calculation has been completed, it is at the H level, and when it has not been completed, it is at the L level. If the flag is at the L level, the process proceeds to step # 107, and an offset compensation calculation is performed so that the output of the vibration gyro 501 falls within the dynamic range (avoids saturation) and is output to a predetermined target value. The detailed operation will be separately described based on the flowchart of FIG. After this calculation, the process proceeds to step # 118.
[0030]
If the flag is at the H level, the offset compensation calculation has been completed, so that the process proceeds from step # 106 to step # 108 to determine the image stabilization operation start flag. When the start of the image stabilization operation is instructed, it is at the H level, and when not instructed, it is at the L level. If the flag is at the L level, the process proceeds to step # 109, and the first determination / control unit 520 performs first determination and control of the amplified output for the vibration gyro 1. The anti-vibration operation start flag referred to in step # 108 is determined in the control in step # 109. That is, an instruction to start the image stabilization operation is issued based on the first determination result. The reason for performing the first determination and the detailed operation will be described separately based on the flowchart of FIG. Thereafter, the process proceeds to step # 118.
[0031]
If it is determined in step # 108 that the flag is at the H level, since the image stabilization operation has started, the process proceeds to step # 110, where the second determination operation state after the start of the image stabilization operation is reflected. The determination end flag is determined. If the second determination is finished, it is at the H level, and if not finished, it is at the L level. If the flag is at the L level, the process proceeds to step # 111, and in order to further increase the accuracy of the determination, the second determination / control unit 521 determines the second determination and the amplified output of the vibration gyro 1 after the start of the image stabilization operation. Take control. The reason for performing the second determination and the detailed operation will be described separately based on the flowchart of FIG.
[0032]
If the flag is at the H level in step # 110, the second determination is completed, so the process immediately proceeds to step # 112, and a high-pass filter (HPF) calculation is performed to cut the DC component. Then, in the next step # 113, an integral calculation for image stabilization control is performed, and converted into an image shake angular displacement signal (BURE_DATA). In the subsequent step # 114, the output of the position sensor 510 that detects the position of the correction lens is captured and A / D converted (after conversion = PSD_DATA).
[0033]
In the next step # 115, feedback calculation {(BURE_DATA)-(PSD_DATA)} is performed. In step # 116, a phase compensation calculation is performed in order to obtain a stable control system. In the next step # 117, PWM output is performed from the PWM converter 513 to the coil driver 514. As a result, image stabilization control is performed, and image blur is corrected.
[0034]
If an instruction to start image blur correction is not given in step # 105, the process proceeds to step # 118 as described above. In step # 118, high-pass filter (HPF) calculation, integration calculation initialization, and timers 1 and 2 are cleared. In this step, image blur correction operation is not performed, and the correction lens is energized and held at a predetermined position.
[0035]
Image blur correction control is performed by the above steps # 101 to # 118.
[0036]
Next, the offset compensation calculation in step # 107 of FIG. 3 described above will be described based on the flowchart of FIG.
[0037]
First, in step # 201, it is determined whether or not a setting for outputting an initial output from the D / A conversion unit 507 is made. This is determined by, for example, the H or L level of the flag. If it is not set and output, the process proceeds to step # 202. If it is set, the process immediately proceeds to step # 203.
[0038]
In step # 202, an initial value is set in the D / A converter 507 so that the D / A converter 507 outputs an initial output. Here, as a method for setting the initial value, as described above, for example, the reference voltage value of the sensor is used. Here, setting is made to output about 1.35V. If the reference voltage of the D / A value of the D / A converter 507 is set to 3.0 V for both D / A converters, for example, since it has a resolution of 8 bits = 256 LSB, 1.35V = 115 LSB. The D / A converter 507a is set, and the other D / A converter 507b is set to 0 LSB for the 0 level output.
[0039]
  Next step # 203InThe signal of the vibration gyro 1A / D valueIs determined to be within the dynamic range. Here, if the A / D reference voltage of the A / D converter 505 is 3.6 V, for example, it is determined whether or not the A / D value is 3.5 V or more. If it is 3.5V or higher, the output is close to saturation or is likely to be saturated, so the process proceeds to step # 204. If it is less than 3.5V, the process proceeds to step # 205.
[0040]
In step # 204, since the A / D value does not fall within the dynamic range and is likely to be saturated on the H level side, the D / A conversion unit 507 connected to the non-inverting input terminal of the operational amplifier 502 is high. The output is controlled so that the A / D value is not saturated. The variable amount of the output after amplification is preferably set to a change amount that does not exceed the reference voltage amount of A / D by a single control of the D / A converter. As described above, assuming that the A / D reference voltage of the A / D converter 505 is 3.6 V, for example, a change amount of less than 3.6 V is preferable. This is because the purpose is to first output the saturated output to an arbitrary level that does not saturate, so that the number of voltage changes is as small as possible. Here, when the amplification factor (determined by R3 / R1) of the amplification unit 503 is set to 64 times, for example, if the non-inverting input terminal of the operational amplifier 502 is changed by ΔVref, the amplified output (output before A / D conversion) is
(Amplification factor of amplification section 503 + 1) × ΔVref = 65 × ΔVref
Only changes. If the output change amount after amplification is set to 3.0V, for example, ΔVref = 0.0462V. Therefore, if the output of the D / A converter 507 is changed by “ΔVref = 0.0462V”, the amplified output will change by 3.0V. Since the D / A converters 507a and 507b of the D / A converter 507 have a resolution of “8 bits = 256 LSB”, the set value is changed by “0.0462V≈4 LSB”. Here, “0.0462V≈4LSB” is subtracted from the current set value of the D / A converter 507a and set. On the other hand, the other D / A converter 507b is left without doing anything. As a result, the amplified output is reduced by 3.0V.
Thereafter, the offset compensation calculation is temporarily terminated.
[0041]
In step # 205, it is determined whether or not the A / D value is 0.1V or more. If it is 0.1 V or more, the output is not saturated and is within the dynamic range, so the process proceeds to step # 207. On the other hand, if it is 0.1 V or less, there is a high possibility that it is saturated to the L level side, so the routine proceeds to step # 206.
[0042]
Proceeding to Step # 206, since the A / D value does not fall within the dynamic range and is likely to be saturated to the H level side, the D / A converter connected to the non-inverting input terminal of the operational amplifier 502 The output of 507 is changed to control the output so that the A / D value is not saturated. Here, only the D / A converter 507a is set by adding 0.0462V≈4LSB to the current set value. On the other hand, the other D / A converter 507b is left without doing anything. This increases the amplified output by 3.0V. Thereafter, the offset compensation calculation is temporarily terminated.
[0043]
  In other words, by performing step # 204 or # 206 a plurality of times, saturation of the amplified output is avoided (the processing of steps # 204 and # 206 is performed by the output saturation avoidance control unit).506aIs). In this step, only the D / A converter 507a is changed, and the coarse adjustment is performed so that the amplified output is within the dynamic range.
[0044]
Proceeding to the next step # 207, since the A / D value is 0.1V or more and less than 3.5V, the sensor amplification output exists within the dynamic range where it is not saturated at this point. Then, it is determined whether or not the output is within a target value, for example, 1.8V ± 0.1V. Here, it is set within the target value ± 0.1 V, but may be limited to a narrower range. If it is within the range, the process proceeds to step # 211, and if it is near the target value, the sensor offset compensation calculation is completed. Therefore, the offset compensation calculation end flag is set to H. If it is out of the range, the process proceeds to step # 208.
[0045]
When the process proceeds to step # 208, the output is not saturated, but the deviation from the target value is large, so the output of the D / A conversion unit 507 is controlled to output the target value. First, the deviation amount X of the current A / D value from a target value, for example, 1.8V
X = (target voltage−A / D value) = (1.8V−A / D value)
Calculate In the next step # 209, a data table (in the control data storage unit 506b) that stores output change amount data of the D / A converters 507a and 507b for outputting the target value corresponding to the value of X in advance. Control data (control data of D / A converter 507a: ± αLSB, control data of D / A converter 507b: ± βLSB) corresponding to the value of X.
[0046]
In the next step # 210, the outputs of the D / A converters 507a and 507b are changed based on both control data (± αLSB, ± βLSB). In other words, the output value within the dynamic range is output to the target value or its vicinity by the steps # 209 and # 210 (the processing of the steps # 209 and # 210 is performed by the data selection / control unit). 506c).
[0047]
The control resolution is summarized as follows: The output resolution of the D / A converter itself is 8 bits and the reference voltage is 3.0V, so it is 0.0117V / LSB. However, each D / A converter can be controlled independently. By doing so, it becomes possible to control with higher precision resolution.
[0048]
  In this embodiment, the amplified output resolution is
  {Resistor R4 / (resistor R4 + resistor R5)} × 0.0117V / LSB
                                        ×(Amplification factor of amplification unit 503 + 1)
It becomes. For example, if “R4: R5 = 4.7: 510” and the amplification factor of the amplification unit 503 are 64, the minimum control resolution of the amplified output is 0.00696 V, which can be controlled with high accuracy. If it is desired to control with a finer resolution, the resistance ratio between the resistors R4 and R5 may be set higher.
[0049]
Through the above steps # 201 to # 211, the sensor offset component is compensated and the output is output near the target value.
[0050]
Next, the first determination and control in step # 109 of FIG. 3 described above will be described.
[0051]
In this first determination, it is determined what state the amplified output of the vibration gyro 1 after the offset compensation calculation is in for a predetermined time. When the output fluctuation for a predetermined time exceeds the predetermined range, there is a high possibility that the offset compensation calculation has been performed while the apparatus is shaken greatly, and there is a possibility that accurate offset compensation has not been performed. In such a case, the output of the vibration shyro 1 is saturated after the apparatus becomes stable thereafter, and vibration detection may not be possible. If the output fluctuation falls within a predetermined range within a predetermined time, it is determined that the state is relatively stable and almost accurate offset compensation calculation is performed, and the image stabilization operation can be started.
[0052]
Further, in the determination time setting, if the determination time is lengthened, the determination accuracy is increased accordingly, but conversely, the start-up time of the image stabilization operation is lengthened. Therefore, here, the time for starting up the vibration isolating operation during normal hand-held support is emphasized, and the time is not set so long. Hereinafter, a description will be given based on the flowchart of FIG.
[0053]
In step # 301, it is determined whether or not the A / D value is output within, for example, 1.8 ± 0.3V. The determination range here is preferably set to a value slightly larger than the normal camera shake amount. If it is not within the predetermined range, it is determined that the apparatus is being shaken, and the process proceeds to step # 302. If it is within the predetermined range, the process proceeds to step # 303.
[0054]
In step # 302, since the output is not within the predetermined range, the timer 1 is cleared, and the offset compensation calculation end flag is set to the L level so that the offset compensation calculation is performed again. Thereafter, the process proceeds to step # 107 in FIG. 3 to perform an offset compensation calculation.
[0055]
On the other hand, when the process proceeds to step # 303, since the output is within the predetermined range, the timer 1, which is the first determination time timer, is counted up. Then, in the next step # 304, it is determined whether or not the timer 1 has passed, for example, 200 msec. If the predetermined time has elapsed, the process proceeds to step # 305. If not, the first determination and control are terminated, and the process proceeds to step # 118 in FIG.
[0056]
  Proceeding to step # 305,Within the predetermined criteria, that isPredetermined judgment timeofSince the output is within the predetermined determination range, the image stabilization operation start flag for instructing the image stabilization operation start is set to the H level.
[0057]
The first determination and control are performed by the above steps # 301 to # 305 (the above steps # 301, # 303, and # 304 are the first determination processing, and the above steps # 302 and # 305 are the first control). Respectively).
[0058]
Next, the second determination and control in step # 111 of FIG. 3 described above will be described.
[0059]
Here, the reason why the second determination is continued after the first determination is that the first determination is set to a relatively short determination time with an emphasis on the image stabilization operation start-up time, This is because the accuracy of the first determination is slightly lowered. Although it is determined in the first determination that the device is being shaken, the determination condition is satisfied in some cases even though the device is being shaken (steps # 301 → # in FIG. 5). 303). Therefore, the second determination is also made as a countermeasure in that case. The determination time setting here is set slightly longer than the determination time of the first determination.
[0060]
Hereinafter, a description will be given based on the flowchart of FIG.
[0061]
In step # 401, it is determined whether or not the A / D value is output within, for example, 1.8 ± 1.0V. The setting of the determination range is determined in consideration of the detection range in which vibration can be detected during normal hand-holding, and the maximum allowable deviation from the output target value. If it is not within the predetermined range, it is determined that the apparatus is still shaken largely and is not stable, and the process proceeds to step # 402. If it is within the predetermined range, the process proceeds to step # 403.
[0062]
In step # 402, since the output is not within the predetermined range, the timers 1 and 2 are cleared, and the offset compensation calculation end flag is set to the L level so that the offset compensation calculation is performed again. Furthermore, the image stabilization operation start flag is also set to L level, and the image stabilization operation is temporarily interrupted. For example, the correction lens is set in the energization holding state. Thereafter, the process proceeds to step # 107 in FIG. 3 to perform an offset compensation calculation.
[0063]
In step # 403, since the output is within the predetermined range, the timer 2, which is the second determination time timer, is counted up. Then, in the next step # 404, it is determined whether or not the timer 2 has passed, for example, 1.0 sec. If the predetermined time has elapsed, the process proceeds to step # 405, and if not, the second determination and control are terminated, and the process proceeds to step # 112 in FIG.
[0064]
  When proceeding to step # 405, a predetermined determination timeofSince the output is within the predetermined determination range, the second determination end flag is set to the H level.
[0065]
By the above steps # 401 to # 405, the second determination and control are performed (the above steps # 401, # 403, # 404 are the second determination processing, and steps # 402, # 405 are the second determination results. Corresponding to the control based on each).
[0066]
Various types of devices can be obtained by storing the predetermined determination time and the predetermined determination range in the first determination and the predetermined determination time and the predetermined determination range in the second determination in a rewritable storage means. For example, it is possible to set an optimum determination time and determination range. For example, a setting that emphasizes the anti-vibration operation rise time or a setting with higher determination accuracy can be easily set from the outside. In addition, the second determination time is longer than the first determination time, and the second determination range is set to be wider than the first determination range, but is not limited thereto, The second determination time may be the same as or longer than the first determination time, and the second determination range may be set wider or the same as the first determination range.
[0067]
According to the above embodiment, the sensor output after the offset compensation calculation is subjected to predetermined determination conditions (specifically, whether the A / D value is within a value slightly larger than the normal camera shake for 200 msec). The image stabilization is started after the determination is made, and the sensor output is set to a predetermined determination condition (specifically, the A / D value is 1.0 msec in the vicinity of the maximum value that can be detected during normal camera shake after the start of the image stabilization). So that the offset compensation operation and the first determination and the second determination are performed again in some cases. ing. Therefore, even if the offset component compensation calculation is performed in the state of panning or large shake, it is possible to avoid the possibility of subsequent vibration detection and not to adversely affect the image shake correction operation. it can.
[0068]
(Modification)
In the above embodiment, an example is shown in which an angular velocity sensor is used as the vibration detecting means. However, any means that can detect vibration, such as an angular acceleration sensor, an acceleration sensor, a speed sensor, an angular displacement sensor, or a displacement sensor. Anything may be used.
[0069]
In addition, as the image blur correction means, a shift optical system that moves an optical member in a plane perpendicular to the optical axis, a light flux changing means such as a variable apex angle, a thing that moves a shooting screen in a plane perpendicular to the optical axis, etc. Any image can be used as long as image blur can be corrected.
[0070]
In addition, the configuration of the invention or embodiment described in each claim may form a single device as a whole, or may be separated or combined with other devices, Or it may be an element constituting the apparatus.
[0071]
【The invention's effect】
As described above, according to the first aspect of the present invention, it is possible to provide a vibration detection apparatus that can accurately detect vibration without saturating the output of the vibration detection means.
[0072]
According to the second aspect of the present invention, even if the apparatus performs the calculation of removing the offset component superimposed on the shake signal in the panning state or the large shake state, it may adversely affect the subsequent image shake correction operation. Therefore, it is possible to provide a non-image blur correction device.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an electrical configuration of a single-lens reflex camera according to an embodiment of the present invention.
FIG. 2 is a block diagram illustrating a specific circuit configuration of a main part according to an embodiment of the present invention.
FIG. 3 is a flowchart illustrating an image blur correction interrupt control operation according to an embodiment of the present invention.
FIG. 4 is a flowchart showing details of an offset compensation calculation in one embodiment of the present invention.
FIG. 5 is a flowchart showing details of first determination and control in an embodiment of the present invention.
FIG. 6 is a flowchart showing details of second determination and control in the embodiment of the present invention.
FIG. 7 is a block diagram showing a specific circuit configuration of a main part of a part related to conventional image blur correction.
FIG. 8 is a diagram showing an example of sensor output at rest and during panning operation.
[Explanation of symbols]
101 Lens microcomputer
102 Shake correction system
106 Runout sensor
108 Shake correction drive system
117 Camera microcomputer
501 Vibrating gyro
503 Amplifier
504 Lens microcomputer
506 Offset removal means
507 D / A converter
520 First determination / control unit
521 Second determination / control unit

Claims (4)

Vibration detecting means for detecting vibration, means for outputting a correction voltage from which the offset component of the output of the vibration detecting means has been removed, and offset for removing the offset component of the output of the vibration detecting means based on the correction voltage in image blur correction device having a removal means, and
After operating the offset removal means, it is determined whether the output from the means for outputting the correction voltage is within the first determination range within the first determination time, and within the determination condition. For example, if the start of the image stabilization operation is instructed and the condition is not within the determination condition, the offset removing unit is operated again, and determination is made as to whether it is within the first determination range within the first determination time. First determination and control means for performing again,
It operates after instructing the start of the image stabilization operation, and determines whether the output of the comparison means is within the second determination range within the second determination time. performs oscillation operation, unless within the said determination condition, temporarily interrupting the stabilization operation, have a, a second determination and control means for operating again the offset removing means,
The image blur correction apparatus characterized in that the second determination time is longer than the first determination time, and the second determination range is wider than the first determination range . 2. The image blur correction apparatus according to claim 1 , wherein the image stabilization operation is to perform image blur correction by driving an image blur correction unit based on an output of the vibration detection unit. An interchangeable lens comprising the image blur correction device according to claim 1. A camera comprising the image blur correction device according to claim 1.

Images